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# Pouring water I.

## 49 posts in this topic

I like that with a 3 liter container and a 5 liter container you can effectively measure out any (non-fractional) number of liters... only up to 8 liters if you can only use the two containers

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If you had a way to measure how much you were filling and pouring out, why wouldn't you just go ahead and put four liters into the five liter bowl. Or just fill it up and pour out a liter. Why waste water? I see no point in the three liter bowl.

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It's more difficult to read the responses than come up with a solution yourself. That's because it is difficult to write an answer that is easy to read. I don't think I've made it any easier but I've given it a shot.

Fill the 5L bowl, then fill the 3L bowl with water out of the 5L bowl to leave 2L in the 5L bowl.

Dump the 3L bowl and pour the 2L of water from the 5L bowl into the 3L bowl. You now have 2L of water in the 3L bowl (room for 1 more)

Fill the 5L bowl again and then fill the 3L bowl with water out of the 5L bowl. Tadah!!! 5 - 1 = 4.

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Pouring water I. - Back to the Water and Weighing Puzzles

If you had a 5-litre and a 3-litre bowl and access to water. How would you measure exactly 4 litres?

Pouring Water I. - solution

Fill the 5-litre bowl and overspill water to the 3-litre bowl, which you empty afterwards. From the 5-litre bowl overspill the 2 remaining litres to the 3-litre bowl. Refill the 5-litre bowl and fill in the 3-litre bowl (with 1 litre), so there stay the 4 required litres in the 5-litre bowl.

That's a good answer but try measuring four liters without wasting any water. Assume there is a drought. The solution is possible.

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That's a good answer but try measuring four liters without wasting any water. Assume there is a drought. The solution is possible.
I forgot to mention that you must assume that the bowls are the same sizea although not same in volume.

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My first answer was the 3-litre bowl method. But, just tought to the details:

Half method

You get 4 litres, without spilling any water. Inaccuracy: paralax measurement

3-litre bowl method

Wasting 5 litres, you get 4 litres

5-litre bowl method

Wasting 3 litres, you get 7 litres

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Pour water in half of each bowl. So you have 1.5 litre ( 3Litre bowl) 2.5 ( 5 litre bowl)

Then pour the 1.5 litre on the 2.5 litre, thus you have 4 litre. <!-- s:lol: --><!-- s:lol: -->

Why not just fill the 3L bowl then pour that into the 5L bowl then add 1L to the 3L and pour that into the 5L bowl...there's 4L

But, if they are marked...Find the 4L mark on the 5L bowl and fill it to that mark...LOL....again, there's 4L

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Perhaps a few more steps--more wasting of water too. But it works.

1) Fill the 3. Pour it into the 5.

2) Fill the 3 again. Pour 2 into the 5. 1 remains in the 3.

3) Empty the 5. Pour the 1 from the 3 into the 5.

4) Fill the 3 again. Pour it into the 5 that already has 1 in it. Voila!

thats how i did it

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You can't mark the water line since this is not exact. Do the following:

1. Fill 5 liter and pour into 3 liter container leaving 2 liters (in the 5 liter container)

2. Empty 3 liter container (no rules about emptying out water) and pour the 2 liters from the 5 into the 3 liter container leaving 1 liter of head space.

3 Fill 5 liter and pour as much as the remainder of the 3 liter will handle (1 liter from step 2) leaving 4 liters exactly in the 5 liter contain. Drink the rest of the water in the 3 liter container

Yours is the best answer I've seen so far.

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Doesn't work that way. If you were able to pour out only 2 units of water from the 3 unit bowl (as stated in line 2) then why not just do that twice, and you would have 4 parts. Point of the riddle is that you are not able to Eyeball 2 parts (meaning the bowls must not be marked or there would be no point for the riddle) You need to figure out a way to accurately measure 4 parts Without Guesswork...

Best I can figure is like this.

Fill the 5 unit bowl. Fill the 3 unit bowl from the 5 unit bowl leaving 2 units in the 5 unit bowl. Mark the 2 unit water line in the 5 unit bowl. Empty the 3 unit bowl. Transfer the pre measured 2 units from bowl 5 into bowl 3. Now bowl 3 has 2 units of water in it for sure! Refill the 5 unit bowl to your mark (2 units) and the dump the other 2 units in the other bowl into that one. B. I. N. G. O and BINGO was her NAME-----O

But that's assuming that you were able to mark the bowls, and I do not think that that is allowed in the rules. So it's still not really valid..lol

I am sorry but it does work that way Veracity.

The reason that it is possible to pour out only two units on line 2 is because there is already 3 units in the 5 unit bowl because you poured 3 units in it the first line. If there is already three units in the 5 unit bowl then obviously you can only pour another 2 units into it. At no point does there need to be any marking for 2 units - this person has it worked out different to the answer given and is totally correct. If you pour 2 units out of 3 units that leaves 1 unit - empty the five unit bowl - put the one unit in it and then add 3 more units from the 3 unit bowl - well done loserfreak!

I agree with both methods.

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2 e.z.

just take the 5 liter container, fill and pour 3 liters into the 3 liter container.

Empty remaining water into bowl.

Repeat.

presto.

the bowl has 4 liters.

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there could be other solution to this problem.

1) Fill the 5. Pour it into the 3. so 5 has 2 ltrs in it.

2) Empty 3. pour 2 ltrs from 5 to 3.

3) Fill 5. then pour 5 to 3, 3 needs only 1ltr to become full.

4) So, in 5, we will have exactly 4ltrs. Yooooohoooooo !!!!

regards,

Milind.

______________________________________________________

Doesn't work that way. If you were able to pour out only 2 units of water from the 3 unit bowl (as stated in line 2) then why not just do that twice, and you would have 4 parts. Point of the riddle is that you are not able to Eyeball 2 parts (meaning the bowls must not be marked or there would be no point for the riddle) You need to figure out a way to accurately measure 4 parts Without Guesswork...

Best I can figure is like this.

Fill the 5 unit bowl. Fill the 3 unit bowl from the 5 unit bowl leaving 2 units in the 5 unit bowl. Mark the 2 unit water line in the 5 unit bowl. Empty the 3 unit bowl. Transfer the pre measured 2 units from bowl 5 into bowl 3. Now bowl 3 has 2 units of water in it for sure! Refill the 5 unit bowl to your mark (2 units) and the dump the other 2 units in the other bowl into that one. B. I. N. G. O and BINGO was her NAME-----O

But that's assuming that you were able to mark the bowls, and I do not think that that is allowed in the rules. So it's still not really valid..lol

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I think instead of using "water" we should be using "gold dust." And it's your gold dust you're pouring in to the bowls and jars. Maybe there wouldn't be any more "eye balling" levels and no more "over spill."

Edited by firepumpguy

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5 & 3 size bowls, resolve 4

A=5 size

B=3 size

A - B

is

0 - 0

Fill A(+5)

5 - 0

Pour A(-3) in to B(+3)

2 - 3

Dump B(-3)

2 - 0

Pour A(-2) in to B(+2)

0 - 2

Fill A(+5)

5 - 2

Pour A(-1) in to B(+1)

4 - 3

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Perhaps a few more steps--more wasting of water too. But it works.

1) Fill the 3. Pour it into the 5.

2) Fill the 3 again. Pour 2 into the 5. 1 remains in the 3.

3) Empty the 5. Pour the 1 from the 3 into the 5.

4) Fill the 3 again. Pour it into the 5 that already has 1 in it. Voila!!

this way is correct

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I have seen a few answers that would work but would waste water.

Here's a method that would require you to waste zero water and allow you to avoid marking or partially filling any bowl.

Place the 3 unit bowl into the 5 unit bowl with the rims in the same plane and fill the 5 unit bowl. This means that you are only filling the space in between the two bowls, thus giving you 2 units because 3 of the 5 units in the 5 unit bowl are taken up by the 3 unit bowl.

Then simply remove the 3 unit bowl and pour the 2 units of water from the 5 unit bowl into the 3 unit bowl.

Then simply repeat the first step filling the 5 unit bowl with the 3 unit bowl placed in it. Then pour the 2 units from the 3 unit bowl into the 5 unit bowl that has the second 2 units in it.

Thus you now have 4 units EXACTLY of water in the 5 unit bowl without wasting any water or partially filling anything.

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I have seen a few answers that would work but would waste water.

Here's a method that would require you to waste zero water and allow you to avoid marking or partially filling any bowl.

Place the 3 unit bowl into the 5 unit bowl with the rims in the same plane and fill the 5 unit bowl. This means that you are only filling the space in between the two bowls, thus giving you 2 units because 3 of the 5 units in the 5 unit bowl are taken up by the 3 unit bowl.

Then simply remove the 3 unit bowl and pour the 2 units of water from the 5 unit bowl into the 3 unit bowl.

Then simply repeat the first step filling the 5 unit bowl with the 3 unit bowl placed in it. Then pour the 2 units from the 3 unit bowl into the 5 unit bowl that has the second 2 units in it.

Thus you now have 4 units EXACTLY of water in the 5 unit bowl without wasting any water or partially filling anything.

This doesn't work because it fails to factor in the volume of water displaced by the actual volume of the 3 litre bowl that you place in the 5 litre bowl.

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This came to my mind right away I read all your and didn't see it. It seems so easy I don't trust myself LOL.

You have a 5ltr bowl and a 3 ltr bowl trying to measure out 4ltrs of water.

Why don't you fill the 3ltr bowl up with water. Being careful not to spill.

Pour the water into the 5ltr bowl. Repeat this, fill the 3ltr bowl up again

with water pour all the water that will fit into the 5 ltr bowl. Thus, leaving

1 ltr of water (3+3=6) in the 3 ltr bowl. pour out the 5 ltr bowl of water.

Pour the 1 ltr of water from the 3 ltr bowl into the 5 ltr bowl fill the 3 ltr

bowl with water again and pour this water in the 5ltr bowl adding it to the

1 ltr of water that is already in the 5 ltr bowl. Now we have 4ltrs of water

in the 5 ltr bowl.

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Why not fill both containers fully. 8 liters then pour out half of each 2.5 amd 1.5 respectively then add the 1.5 in the 3 liter to the 2.5 in the 5 liter to equal 4.

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Why not fill both containers fully. 8 liters then pour out half of each 2.5 amd 1.5 respectively then add the 1.5 in the 3 liter to the 2.5 in the 5 liter to equal 4.

Why not just fill them half full to begin with? Or how about:

fill the 5 pour it into the 3

Dump the 3 and pour the remaining 2 from the 5 into it

fill the 5 and then top up the 3

you should have 4 in the 5 now

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easy u get a four-litre container and fill

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(1) fill the 5-Liter bowl

(2) using (1), decant 3L into 3-L bowl; this leaves 2L in the 5-L bowl

(3) in any available ample-sized, "other" container, pour the 2L from the 5-L bowl

(4) reuse water from 3-L bowl into 5-L bowl and fill 5-L bowl to 5L

(5) repeat (2) and (3) to get 4-L in the "other" container

wastes 2L!!!

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Fill up the 5-liter bowl and pour it into the 3-liter bowl. Empty the 3-liter bowl and pour the rest of the water from the 5-liter bowl into it. Then, fill up the 5 liter bowl again. Pour water into the 3-liter bowl so that it is full. You should then have 4 liters in the 5-liter bowl.

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No matter what shape the five-liter container and the three-liter containers are you can tilt them while filling them from the bottom left of the base of the container to the upper right lip of the container. By doing so, you have obtained 50% capacity. Half of the five-liter container holds 2.5 liters. Half of the three-liter container contains 1.5 liters. Once you have filled both containers in this manner, pour the liquid from the three-liter container into the five-liter container and you have the desired four liters!